The University of Chicago (UC)-Illinois State Psychiatric Institute (ISPI) MHCRC provides core resources and pilot study support for a multidisciplinary, longitudinal study of biology, behavior and psychopathology in schizophrenia, affective disorders, and the controversial schizoaffective states. The MHCRC utilizes 30 in-patient research beds and two out-patient clinics at ISPI, laboratory facilities at ISPI and the UC, and staff from the UC, ISPI, Michael Reese Hospital, and Northwestern Medical School to conduct its studies and carry out training functions. Patients are evaluated in standardized manner with an expanded Present State Examination, SADS-change interviews, a newly developed Psychiatric History Schedule, as well as other means. A computerized, multi-system diagnostic approach is integral to a major effort in diagnostic nosology focused on clarification of the relationship between the so-called schizoaffective psychoses and the Kraepelinian psychoses. The original MHCRC emphasis on neuroendocrine (prolactin, growth hormone) and biomedical studies (platelet MAO, serum CPK, DBH) will be supplemented by new investigators working in psychophysiology (brain blood flow, laterality, evoked response), psychopharmacology (peptides, novel anti-depressants lithium), neuropsychology, virology and biochemistry (receptors for neurotransmitters in platelets and red blood cells, prostoglandins). Relevant pre-clinical biological studies are also supported by MHCRC funds. Biological, psychological, and behavioral data collected at 1, 3, and 5 year follow-up are integrated with data obtained during initial hospitalization. Family history and family interview studies will also be conducted in selected areas. Students from every area on clinical practice, pre- and post-doctoral fellows, and scientists from the U.S. and abroad have opportunities for intensive research and clinical experiences by participation in MHCRC projects.